Atmospheric trace gas measurements using ion mobility spectrometer

Abstract. Ion mobility spectrometer (IMS) was implemented to measure gas phase compounds from ambient air in order to study the suitability of the technique for on-line atmospheric measurements. The measurements took place at the SMEAR II station in Hyytiälä, Finland during spring periods on 2008 and 2009. We were able to separate several different atmosphere related ion mobility peaks form the measured ion mobility distributions. The hypothetic origins of these peaks are discussed accompanying the comparison with earlier trace gas measurements by different techniques. The potential of the IMS for atmospheric studies utilizing the concept used here was found out to be in monitoring the overall cleanness of prevailing atmospheric conditions as well as fast detection of the changes of those conditions. With further developing of the technique based on experience gathered in this study the IMS could be tuned to better respond to current measurement needs in atmospheric studies.